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US8146339B2 - Steel cord for reinforcing rubber article and pneumatic radial tire - Google Patents

Steel cord for reinforcing rubber article and pneumatic radial tire Download PDF

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Publication number
US8146339B2
US8146339B2 US12/092,198 US9219806A US8146339B2 US 8146339 B2 US8146339 B2 US 8146339B2 US 9219806 A US9219806 A US 9219806A US 8146339 B2 US8146339 B2 US 8146339B2
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United States
Prior art keywords
cord
steel
filaments
steel cord
belt layer
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US12/092,198
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English (en)
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US20090283193A1 (en
Inventor
Shoji Hayashi
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Bridgestone Corp
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Bridgestone Corp
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Publication date
Priority claimed from JP2005315811A external-priority patent/JP4716846B2/ja
Priority claimed from JP2005359704A external-priority patent/JP2007162163A/ja
Application filed by Bridgestone Corp filed Critical Bridgestone Corp
Assigned to BRIDGESTONE CORPORATION reassignment BRIDGESTONE CORPORATION ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: HAYASHI, SHOJI
Publication of US20090283193A1 publication Critical patent/US20090283193A1/en
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    • D—TEXTILES; PAPER
    • D07—ROPES; CABLES OTHER THAN ELECTRIC
    • D07B—ROPES OR CABLES IN GENERAL
    • D07B1/00—Constructional features of ropes or cables
    • D07B1/06—Ropes or cables built-up from metal wires, e.g. of section wires around a hemp core
    • D07B1/0606—Reinforcing cords for rubber or plastic articles
    • D07B1/062—Reinforcing cords for rubber or plastic articles the reinforcing cords being characterised by the strand configuration
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
    • B60C9/00—Reinforcements or ply arrangement of pneumatic tyres
    • B60C9/0007—Reinforcements made of metallic elements, e.g. cords, yarns, filaments or fibres made from metal
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
    • B60C9/00—Reinforcements or ply arrangement of pneumatic tyres
    • B60C9/18—Structure or arrangement of belts or breakers, crown-reinforcing or cushioning layers
    • B60C9/20—Structure or arrangement of belts or breakers, crown-reinforcing or cushioning layers built-up from rubberised plies each having all cords arranged substantially parallel
    • B60C9/2003—Structure or arrangement of belts or breakers, crown-reinforcing or cushioning layers built-up from rubberised plies each having all cords arranged substantially parallel characterised by the materials of the belt cords
    • B60C9/2006—Structure or arrangement of belts or breakers, crown-reinforcing or cushioning layers built-up from rubberised plies each having all cords arranged substantially parallel characterised by the materials of the belt cords consisting of steel cord plies only
    • D—TEXTILES; PAPER
    • D07—ROPES; CABLES OTHER THAN ELECTRIC
    • D07B—ROPES OR CABLES IN GENERAL
    • D07B1/00—Constructional features of ropes or cables
    • D07B1/06—Ropes or cables built-up from metal wires, e.g. of section wires around a hemp core
    • D07B1/0606—Reinforcing cords for rubber or plastic articles
    • D07B1/062—Reinforcing cords for rubber or plastic articles the reinforcing cords being characterised by the strand configuration
    • D07B1/0626—Reinforcing cords for rubber or plastic articles the reinforcing cords being characterised by the strand configuration the reinforcing cords consisting of three core wires or filaments and at least one layer of outer wires or filaments, i.e. a 3+N configuration
    • D—TEXTILES; PAPER
    • D07—ROPES; CABLES OTHER THAN ELECTRIC
    • D07B—ROPES OR CABLES IN GENERAL
    • D07B2201/00—Ropes or cables
    • D07B2201/20—Rope or cable components
    • D07B2201/2001—Wires or filaments
    • D07B2201/2006—Wires or filaments characterised by a value or range of the dimension given
    • D—TEXTILES; PAPER
    • D07—ROPES; CABLES OTHER THAN ELECTRIC
    • D07B—ROPES OR CABLES IN GENERAL
    • D07B2201/00—Ropes or cables
    • D07B2201/20—Rope or cable components
    • D07B2201/2015—Strands
    • D07B2201/2016—Strands characterised by their cross-sectional shape
    • D07B2201/2018—Strands characterised by their cross-sectional shape oval
    • D—TEXTILES; PAPER
    • D07—ROPES; CABLES OTHER THAN ELECTRIC
    • D07B—ROPES OR CABLES IN GENERAL
    • D07B2201/00—Ropes or cables
    • D07B2201/20—Rope or cable components
    • D07B2201/2015—Strands
    • D07B2201/2022—Strands coreless
    • D—TEXTILES; PAPER
    • D07—ROPES; CABLES OTHER THAN ELECTRIC
    • D07B—ROPES OR CABLES IN GENERAL
    • D07B2201/00—Ropes or cables
    • D07B2201/20—Rope or cable components
    • D07B2201/2015—Strands
    • D07B2201/2023—Strands with core
    • D—TEXTILES; PAPER
    • D07—ROPES; CABLES OTHER THAN ELECTRIC
    • D07B—ROPES OR CABLES IN GENERAL
    • D07B2201/00—Ropes or cables
    • D07B2201/20—Rope or cable components
    • D07B2201/2015—Strands
    • D07B2201/2024—Strands twisted
    • D07B2201/2027—Compact winding
    • D07B2201/2028—Compact winding having the same lay direction and lay pitch
    • D—TEXTILES; PAPER
    • D07—ROPES; CABLES OTHER THAN ELECTRIC
    • D07B—ROPES OR CABLES IN GENERAL
    • D07B2201/00—Ropes or cables
    • D07B2201/20—Rope or cable components
    • D07B2201/2015—Strands
    • D07B2201/2024—Strands twisted
    • D07B2201/2029—Open winding
    • D—TEXTILES; PAPER
    • D07—ROPES; CABLES OTHER THAN ELECTRIC
    • D07B—ROPES OR CABLES IN GENERAL
    • D07B2201/00—Ropes or cables
    • D07B2201/20—Rope or cable components
    • D07B2201/2047—Cores
    • D07B2201/2052—Cores characterised by their structure
    • D07B2201/2059—Cores characterised by their structure comprising wires
    • D07B2201/206—Cores characterised by their structure comprising wires arranged parallel to the axis
    • D—TEXTILES; PAPER
    • D07—ROPES; CABLES OTHER THAN ELECTRIC
    • D07B—ROPES OR CABLES IN GENERAL
    • D07B2401/00—Aspects related to the problem to be solved or advantage
    • D07B2401/20—Aspects related to the problem to be solved or advantage related to ropes or cables
    • D07B2401/206—Improving radial flexibility
    • D—TEXTILES; PAPER
    • D07—ROPES; CABLES OTHER THAN ELECTRIC
    • D07B—ROPES OR CABLES IN GENERAL
    • D07B2501/00—Application field
    • D07B2501/20—Application field related to ropes or cables
    • D07B2501/2046—Tyre cords
    • D—TEXTILES; PAPER
    • D07—ROPES; CABLES OTHER THAN ELECTRIC
    • D07B—ROPES OR CABLES IN GENERAL
    • D07B2501/00—Application field
    • D07B2501/20—Application field related to ropes or cables
    • D07B2501/2076—Power transmissions

Definitions

  • the present invention relates to a steel cord for reinforcing rubber article, and a pneumatic radial tire (hereinafter, these may be also simply referred to as “cord” and “tire”, respectively). More specifically, the present invention pertains to a steel cord for reinforcing rubber article suitably used for the reinforcement of a rubber article such as a pneumatic radial tire, and to a pneumatic radial tire using the same. The present invention also concerns a pneumatic radial tire having superior steering stability, used for a high performance passenger car or the like.
  • the pneumatic radial tire has a carcass, as a framework, extending toroidally between a pair of bead parts, and on the outside in the radial direction of the tire, there is provided a belt layer comprising a rubberized steel cord, as a reinforcing layer.
  • a steel cord that is high in flexibility and superior in durability is demanded as a reinforcing material for the belt layer, and various studies thereof have been hitherto conducted.
  • important properties necessary for the belt layer to ensure steering stability for a high performance radial tire are high tensile rigidity in the circumferential direction, high in-plane flexural rigidity, and low out-of-plane flexural rigidity.
  • the belt member must have high rigidity in the circumferential direction in order to bear a tension by an internal pressure to thereby exert a hoop effect.
  • the belt layer preferably has high tensile rigidity in the circumferential direction.
  • the belt member since the belt member is subjected to an in-plane bending deformation during cornering, the tire that is smaller in the in-plane bending deformation in the belt creates a larger cornering force, thereby allowing better steering stability to be exercised. Therefore, secondly, the belt layer preferably has high in-plane flexural rigidity.
  • the belt layer undergoes a large bending deformation in the in-plane direction. Due to this deformation, inside the bending deformation, the belt layer is subjected to a large compressive deformation, to thereby cause buckling.
  • an out-of-plane deformation pressure accompanied with the compression decreases, thereby enabling buckling deformation to be inhibited by the internal pressure of the tire.
  • a release of a ground contact pressure is suppressed, resulting in a uniform contact pressure. Therefore, thirdly, the belt layer preferably has low out-of-plane flexural rigidity.
  • the Patent Document 1 sets forth a technique for improving steering property, stability and the like during cornering by using a specific steel cord composed of filaments with a small diameter (filament diameter: 0.06 to 0.10 mm).
  • the Patent Document 2 discloses a tire of which the steel cord is defined by bending resistance and tensile elongation.
  • the Patent Document 3 discloses a tire having a steel code which is composed of predetermined steel filaments and in which the range of values defined by belt flexural rigidity, cord tenacity, and the void amount in a belt cord is defined to be a predetermined range.
  • the Patent Documents 4 to 6 each disclose a steel cord for tire reinforcement which has a predetermined filament structure and in which the range of values defined by cord tenacity, cord elongation at break, and cord flexural rigidity, is regulated to a predetermined range.
  • Each of these techniques in the Patent Documents 1 to 6 is one that applies a multi-stranded cord using extra-fine steel filaments to the belt layer.
  • Patent Document 7 discloses a tire (using a steel cord having a 1 ⁇ n structure composed of 4 or less steel filaments, with the filament diameter being not more than 0.22 mm) wherein the belt is defined by the stranding structure of a belt cord, the filament diameter, and the number of embedded belt cords.
  • Patent Document 9 discloses a tire (using a steel cord having a 1 ⁇ n structure composed of 5 or less steel filaments, with the filament diameter being 0.10 to 0.22 mm) wherein the belt ply of which the belt cord structure and the number of embedded belt cords are defined to be a predetermined ones is arranged via shock-absorbing rubber.
  • Each of these techniques in the Patent Documents 7 to 9 is one which applies a 1 ⁇ n steel cord using five or less small-diameter steel filaments to the belt layer.
  • steel cords each having a 1 ⁇ n structure composed of six or more steel filaments stranded in the same direction at the same stranding pitch, are disclosed in Patent Documents 10, 11, and the like.
  • Patent Document 7 to 9 make a proposition to use a 1 ⁇ n steel cord employing five or less small-diameter filaments as a belt layer.
  • a cord is low in strength per cord, there arises a problem of high-speed durability when the cord is used as a belt reinforcing material for a high performance radial tire.
  • steel cords having a 1 ⁇ n structure composed of six or more steel filaments stranded in the same direction at the same stranding pitch are set forth in Patent Documents 10, 11, and the like.
  • Patent Documents 10, 11, and the like are set forth in Patent Documents 10, 11, and the like.
  • these documents do not disclose a technique for improving steering stability by using this cord as a belt reinforcing material for a high performance radial tire.
  • a first object of the present invention is to provide a steel cord for reinforcing rubber article, superior in durability to conventional steel cords by improving on the cord structure, and to provide a pneumatic radial tire improved in steering stability and durability by using the same.
  • the steel code exhibits higher flexural rigidity in a state of being applied to a tire as a belt reinforcing cord than in a state of being the cord alone. That is, it has been proved that a flexural rigidity reducing effect of using fine filaments has not been sufficiently exerted in the tire, and that there is room for improvement.
  • a second object of the present invention is to solve the above-described problems associated with the conventional arts, and to provide a pneumatic radial tire satisfactorily combining steering stability, durability, and good cost performance required for a high performance radial tire intended for the application to a high performance passenger car.
  • a steel cord for reinforcing rubber article according to the present invention has a 1 ⁇ n structure composed of a plurality of steel filaments stranded in the same direction at the same stranding pitch, the steel cord being characterized in that the number of steel filaments is 6 to 12, and the diameter of the steel filaments is 0.08 to 0.21 mm.
  • the cord according to the present invention preferably has flexural rigidity of 49 to 196 MPa (5.0 to 20.0 kgf/mm 2 ).
  • the number of the steel filaments is 7 to 10, the diameter thereof is 0.10 to 0.20 mm, and the tensile strength thereof is 3200 to 4000 MPa.
  • the outer profile shape of the cord is flat, and that the ratio (D 1 /D 2 ) of the minor axis D 1 of the outer profile shape to the major axis D 2 thereof is 0.5 to 0.8.
  • a first pneumatic radial tire according to the present invention has a carcass, as a framework, extending toroidally between a pair of bead parts, with a crown part of the carcass being reinforced with a belt layer, the first pneumatic radial tire being characterized in that the steel cord for reinforcing rubber article according to the present invention is applied to a cord constituting the belt layer.
  • the flexural rigidity (Ec) of the steel cord for reinforcing rubber article that has been taken out from the belt layer with rubber attached thereto is preferably 49 to 196 MPa (5.0 to 20.0 kgf/mm 2 ). Also, the flexural rigidity (Ec) of the steel cord for reinforcing rubber article that has been taken out from the belt layer with rubber attached thereto, is 1.0 to 1.27 times as high as the flexural rigidity (Er) of the steel cord for reinforcing rubber article, cleared of the rubber.
  • a steel cord for reinforcing rubber article wherein the outer profile shape of the cord is flat, and the ratio (D 1 /D 2 ) of the minor axis D 1 of the outer profile shape to the major axis D 2 thereof is 0.5 to 0.8, is applied to the cord constituting the belt layer, and the steel cord is arranged so that the major axis direction of the cord outer profile shape is along the width direction of the belt layer.
  • the present inventor has analyzed a phenomenon that, when a multi-stranded steel code using conventional small-diameter filaments is applied to a tire as a belt reinforcing cord, this multi-stranded steel code exhibits larger rigidity than that of the code alone, and the present inventor has found the following matter.
  • the present inventor has further conducted a keen study, and has found that a use of the following construction allows a tire combining a desired steering stability, durability, and good cost performance to be realized, and enables the second object of the present invention to be attained.
  • the inventor has achieved a second pneumatic radial tire.
  • the second pneumatic radial tire according to the present invention includes a carcass, as a framework, extending toroidally between a pair of bead parts, and at least one belt layer that is obtained by rubberizing a steel cord composed of a plurality of steel filaments and that is disposed on the outside in the radial direction of a crown part of the carcass, the second pneumatic radial tire being characterized in that the flexural rigidity (Ec) of the steel cord in a state of being buried in the belt layer is not less than 49 MPa nor more than 196 MPa, and simultaneously, the Ec value is 1.0 to 1.27 times as high as the flexural rigidity (Er) of the steel cord alone in a state of not being buried in the belt layer.
  • Ec flexural rigidity
  • the filament diameter of the steel filaments is preferably 0.08 to 0.21 mm, and the number of the steel filaments is preferably 6 to 12.
  • the steel cord is composed of the plurality of steel filaments stranded in the same direction at the same stranding pitch, and is buried in the belt layer, with rubber permeated between the steel filaments. In this case, especially, the steel cord has not a cord structure in which one or more of the steel filaments are encircled by the other steel filaments.
  • the steel cord comprises a core strand composed of one or two of the steel filaments, and a layer of sheath composed of the other steel filaments stranded around the core strand.
  • the core strand is composed of two of the non-stranded steel filaments arranged in parallel to each other.
  • a steel cord for reinforcing rubber article that is superior in durability to conventional steel cords can be realized, and the use of it has enabled the implementation of a pneumatic radial tire improved in steering stability and durability. That is, in order to realize the preferred belt layer properties as described above, conventionally, multi-stranded steel cords using small-diameter filaments have been employed.
  • the cord according to the present invention has a 1 ⁇ n structure composed of a plurality of steel filaments stranded in the same direction at the same stranding pitch, it has advantages of being high in productivity and being capable of production at low cost.
  • good rubber penetration property can be provided.
  • techniques disclosed in the Patent Document 10 and 11 or the like can also be adopted.
  • the use of the above-described construction has made it possible to realize a pneumatic radial tire satisfactorily combining steering stability, durability, and good cost performance required for a high performance radial tire intended for the application to a high performance passenger car.
  • FIG. 1 is a schematic sectional view of a pneumatic radial tire according to an embodiment of the present invention.
  • FIG. 3 is a schematic sectional view of a steel cord for reinforcing rubber article according to an embodiment 1-2 or 2-2 of the present invention.
  • FIG. 4 is a schematic sectional view of a steel cord for reinforcing rubber article according to an embodiment 1-3 of the present invention.
  • FIG. 5 is a schematic sectional view of a steel cord for reinforcing rubber article according to an embodiment 1-4 of the present invention.
  • FIG. 7 is a schematic sectional view of a steel cord used in an embodiment 2-4 of the present invention.
  • FIG. 8 is a schematic sectional view of a steel cord used in an embodiment 2-5 of the present invention.
  • FIG. 9 is a sectional view of a steel cord for reinforcing rubber article according to a conventional example 1-1 or 2-1.
  • FIG. 12 is a sectional view of a steel cord for reinforcing rubber article according to a comparative example 1-1.
  • FIG. 13 is a sectional view of a steel cord for reinforcing rubber article according to a comparative example 1-2 or 2-2.
  • FIG. 14 is a sectional view of a steel cord used in a comparative example 2-1.
  • the steel cord for reinforcing rubber article in the present invention has a 1 ⁇ n structure composed of a plurality of steel filaments stranded in the same direction at the same stranding pitch.
  • the filament diameter is set to 0.08 mm or more, preferably 0.10 mm or more.
  • the number of steel filaments constituting the cord is 6 to 12, preferably 7 to 10.
  • an upper limit of the number of filaments is set to 12, preferably 10.
  • the filament number is under 6, since the cord tenacity is too low under the condition of the filament diameter of 0.08 to 0.21 mm, it is necessary to significantly increase the number of embedded belt cords to thereby densely arrange cords in order to ensure the circumferential rigidity for the belt layer.
  • the number of filaments is set to 6 or more, preferably 7 or more.
  • the brass-plated steel wire used as a filament for steel cord having a diameter on the order of 0.08 to 0.21 mm, ordinarily has a tensile strength value around 3000 MPa.
  • a use of filaments having a tensile strength of preferably 3200 to 4000 MPa, and more preferably 3300 to 4000 MPa facilitates ensuring the circumferential rigidity for the belt layer at a proper density of embedded belt cords.
  • the outer profile shape of the cord is made flat so that the ratio (D 1 /D 2 ) of the minor axis D 1 of the outer profile shape to the major axis D 2 thereof is 0.5 to 0.8.
  • the diameter and the number of steel filaments constituting the cord are defined in the cord having the 1 ⁇ n structure, the other matters are not particularly limited but can be appropriately determined by the common procedure.
  • the stranding pitch of the cord may be on the order of 5.0 to 15.0 mm.
  • the cord according to the present invention can be suitably applied for reinforcing various rubber articles such as tires, industrial belts, and especially can be suitably applied to high performance pneumatic radial tires.
  • FIG. 1 shows a construction example of pneumatic radial tire according to the present invention.
  • the first pneumatic radial tire in the present invention has a carcass 1 as a framework, extending toroidally between a pair of bead parts 11 , with a crown part of the carcass being reinforced with a belt layer 2 , wherein the above-described steel cord for reinforcing rubber article is applied to a cord constituting such a belt layer 2 .
  • the out-of-plane flexural rigidity while sufficiently ensuring the tensile rigidity in the circumferential direction and the in-plane flexural rigidity. This allows a good steering stability to be exerted while ensuring high-speed durability.
  • the steel cord is subjected to a tension, so that distances between filaments are reduced.
  • the flexural rigidity of the steel cord in a state of being actually buried in the belt layer is preferably in a range of 49 to 196 MPa (5.0 to 20.0 kgf/mm 2 ).
  • the flexural rigidity of this steel cord in a state of being actually buried in the belt layer can be evaluated by measuring the flexural rigidity (Ec) of the cord taken out from the belt layer with rubber attached thereto.
  • the change in flexural rigidity of the cord before and after the cord being buried in the belt layer is small.
  • the flexural rigidity (Ec) of the cord that has been taken out from the belt layer with rubber attached thereto is preferably 1.0 to 1.27 times as high as the flexural rigidity (Er) of the cord cleared of the rubber.
  • the flexural rigidity of the cord in the present invention is a value obtained by measuring in a state wherein the cord has been bent 15 degrees from a fulcrum after having been cut to a predetermined length, using a commercial taber flexural rigidity tester (for example, a Toyo Seiki Seisaku-sho, Ltd., digital taber type stiffness tester).
  • a commercial taber flexural rigidity tester for example, a Toyo Seiki Seisaku-sho, Ltd., digital taber type stiffness tester.
  • the flexural rigidity of the cord having a flat outer profile shape is defined to be rigidity (resistance) with respect to bending in the minor axis direction.
  • the flexural rigidity of the steel cord that has been taken out from the belt layer of the tire with rubber attached thereto is measured in a state wherein, after the cord with the rubber attached thereto has been taken out, the thickness of a coating rubber on the cord surface is reduced to about 0.1 to 0.5 mm by chipping away the coating rubber.
  • the flexural rigidity of the cord cleared of the rubber is measured in a state wherein the rubber is completely removed by an organic solvent or the like.
  • the number of filaments in the cord of the present invention is as small as 6 to 12, preferably 7 to 10, the interactions between filaments are small.
  • the change in flexural rigidity of the cord before and after the code being buried in the belt layer can be made small.
  • (1) As a cord structure to adopt an open structure or the like in which rubber is prone to penetrate between filaments. On the promotion of rubber penetration, besides the arts disclosed in the Patent Documents 10 and 11, arts disclosed in the following Patent Documents may be adopted: Japanese Unexamined Patent Application Publication No. 5-302283, Japanese Unexamined Patent Application Publication No. 6-10281, Japanese Unexamined Patent Application Publication No. 6-73673, Japanese Unexamined Patent Application Publication No.
  • Interposing rubber between filaments makes the interactions smaller than the case where filaments make direct contact between them.
  • (2) Regarding cord section to use a single layer structure without a central structure into which rubber is less prone to penetrate (i.e., a structure in which one or more filaments are encircled by the other filaments). By doing this, the interposition of rubber between filaments reliably becomes prone to be realized, and also the number of adjacent filaments becomes as small as two in total on the both sides, i.e., a minimum number.
  • the first tire in the present invention has only to be one in which the above-described steel cord for reinforcing rubber article according to the present invention is applied to the belt layer, whereby effects of enhancing steering stability and durability can be obtained.
  • the other matters such as a specific tire structure, a tire material and the like can be appropriately determined by the common procedure, and are not particularly limited.
  • the second pneumatic radial tire in the present invention includes a carcass 1 as a framework, extending toroidally between a pair of bead parts 11 , and at least one belt layer (in the illustrated example, two crossing belt layers 2 [ 2 a and 2 b ]) obtained by rubberizing a steel cord composed of a plurality of steel filaments, the belt layer being disposed on the outside in the radial direction of the crown part of the carcass 1 .
  • the flexural rigidity (Ec) of the steel cord in a state of being buried in the belt layer 2 to a value of not less than 49 MPa (5.0 kgf/mm 2 ) nor more than 196 MPa (20.0 kgf/mm 2 )
  • a steering stability sufficient for a high performance radial tire is ensured.
  • the flexural rigidity (Ec) of the steel cord in a state of being buried in the belt layer 2 to be 1.0 to 1.27 times as high as the flexural rigidity (Er) of the steel cord alone in a state of not being buried in the belt layer 2 , flexibility of the cord alone is effectively utilized in the tire.
  • the flexural rigidity of the above-described steel cord can also be measured using a commercial taber flexural rigidity tester (for example, the Toyo Seiki Seisaku-sho, Ltd., digital taber type stiffness tester).
  • a commercial taber flexural rigidity tester for example, the Toyo Seiki Seisaku-sho, Ltd., digital taber type stiffness tester.
  • the above-described flexural rigidity of the cord is a value obtained by measuring in a state wherein the cord has been bent 15 degrees from a fulcrum after having been cut to a predetermined length.
  • the flexural rigidity value is defined to be rigidity with respect to bending in the minor axis direction.
  • the flexural rigidity of the steel cord that has been taken out from the belt layer 2 of the tire with rubber attached thereto is measured in a state wherein, after the cord with the rubber attached thereto has been taken out, the thickness of a coating rubber on the cord surface is reduced to about 0.1 to 0.5 mm by chipping away the coating rubber.
  • the flexural rigidity of the steel cord in a state of not being buried in the belt layer is measured in a state wherein rubber on the surface of the steel cord that has been taken out from the belt layer of the tire with the rubber attached thereto, is completely removed by an organic solvent.
  • the flexural rigidity of the steel cord may be measured with respect to a raw cord before being buried in the tire.
  • the code structure of the steel code is not particularly limited, as steel filaments constituting the steel code, for example, ones having a filament diameter of 0.08 to 0.21 mm, preferably 0.10 to 0.20 mm are used.
  • the filament diameter of steel filaments to 0.21 mm or less, preferably 0.20 mm or less, facilitates making the flexural rigidity (Ec) of steel code in a state of being buried in the belt layer 2 to a value of 196 Pa or less.
  • the diameter of the steel filament is under 0.08 mm, since the cord tenacity is too low under the condition of a preferred filament number to be described later, it is necessary to significantly increase the number of embedded cords to thereby densely arrange cords in order to ensure the circumferential rigidity for the belt layer 2 . As a result, a separation between rubber and the cord becomes prone to occur. Otherwise, there arises a risk that high-speed durability may be impaired because of shortage of circumferential rigidity.
  • the number of steel filaments constituting the steel cord is set to 6 to 12, preferably 7 to 10. Why the upper limit of the filament number is set to 12, preferably 10 is because interactions between filaments when the cord is bent, are prone to be larger as the filament number increases.
  • the filament number is under 6, since the cord tenacity is too low under the condition of the above-described preferred filament diameter, it is necessary to significantly increase the number of embedded cords to thereby densely arrange cords in order to ensure the circumferential rigidity for the belt layer 2 . As a result, a separation between rubber and the cord becomes prone to occur. Otherwise, there arises a risk that high-speed durability may be impaired because of shortage of circumferential rigidity.
  • the steel cord having a 1 ⁇ n structure composed of all steel filaments stranded in the same direction at the same stranding pitch, in a state of being buried in the belt layer 2 with rubber permeated between the filaments. Since rubber is interposed between the filaments, by burying the steel cord with rubber permeated between filaments, interactions between filaments when the cord is bent becomes smaller, as compared with the case where filaments directly makes contact with each other. In this 1 ⁇ n single stranded structure, it is easy to provide a structure in which rubber is permeable into the code. For example, by applying an open structure in which excessively patterned filaments are loosely stranded, a structure in which filaments provided with ripple curls are stranded, or the like, rubber permeability can be imparted.
  • a cord structure without a core structure in which one or more steel filaments are encircled by the other steel filaments is employed.
  • the cord structure without a core structure is small in the number of mutually adjacent filaments therein, and therefore, interactions between filaments when the cord is bent, are small.
  • the cord structure without a core structure allows rubber permeation into the cord to be more perfect.
  • the filament number (n) of the core strand is set to 1 or 2, and the number of sheath layer is set to 1. If the filament number (n) of the core strand is 3 or more, in the center of the cord, a closed space into which rubber does not permeate by being encircled by the core filaments, is prone to occur. Also, if the number of sheath layers is 2 or more, it is difficult to cause rubber to permeate into an inside sheath. In this case, more preferably, the number of sheath filaments (m) is set to 5 to 8, thereby providing a structure in which spacings are provided between sheath filaments.
  • the core strand is composed of non-stranded two filaments arranged in parallel to each other. In this case, since the core filaments are not stranded, an interaction between core filaments when the cord is bent, is smaller.
  • a preferred stranding pitch in the second tire according to the present invention is on the order of 5 to 18 mm. If the stranding pitch is under 5 mm, there is a risk of causing breaking of filaments during stranding, and productivity decreases, resulting in cost increase. Conversely, if the stranding pitch is over 18 mm, the stranding angle decreases, so that stranding property incurs a risk of being deteriorated. In addition, there is a drawback of becoming less prone to rubber penetration.
  • the outer profile shape of the steel cord is made flat, and the steel cord is arranged so that the major axis direction of the flat section is along the width direction of the belt layer.
  • the flexural rigidity has anisotropy, so that it is possible to construct a belt layer that is higher in in-plane flexural rigidity and lower in out-of-plane flexural rigidity, as compared with the case where non-flat steel cord is arranged.
  • brass-plated steel wires ordinarily having a tensile strength on the order of 3200 to 4000 MPa, especially 3300 to 4000 MPa can be suitably employed.
  • the circumferential flexural rigidity for the belt layer can be easily ensured at a proper density of embedded belt cords.
  • a steel cord satisfying the above-described conditions can be obtained, and by applying such a steel cord to the belt layer 2 , a pneumatic radial tire superior in steering stability and durability can be realized.
  • structures, specific materials, and the like of the other members constituting the tire are not particularly restricted.
  • a bead core 3 is buried in each of the pair of bead parts 11 , and the carcass 1 is folded from the inside of the tire to the outside thereof around the bead cores 3 , and engaged therewith.
  • a tread part 12 is arranged on the outer periphery of the crown part of the belt layer 2
  • sidewall parts 13 are arranged on the side portions of the carcass 1 , respectively.
  • the cap layers 4 each have a widthwise length covering at least the belt layer 2 , and are each composed of rubberized reinforcing cords arranged substantially in parallel to the tire circumferential direction.
  • the pair of layer tiers 5 each have a widthwise length covering a widthwise end portion on one side of the belt layer, and are each composed of rubberized reinforcing cords arranged substantially in parallel to the tire circumferential direction.
  • the belt structure comprises two layers of crossed steel belt layers 2 a and 2 b (angle: ⁇ 60°), the two cap layers 4 , and the pair of layers 5 (material: nylon), wherein the cap layers 4 and the pair of layers 5 are composed of reinforcing cords arranged substantially in parallel to the tire circumferential direction.
  • test cord was covered with rubber and vulcanized. Then, one end of the test cord was soaked in an aqueous 10 percent solution of NaOH, and after the test cord has been left for 24 hours, “rubber separation length” was measured. If the rubber has permeated the cord up to the inside thereof, the rubber is not separated. Herein, if the separation length is on the order of 10 mm or less, no practical problems occur.
  • test tires were mounted onto four wheels of a passenger car, with an air pressure of 205.8 kPa (2.1 kgf/cm 2 ) charged, and a test driver run this test car on a test course.
  • the steering stability was evaluated by rating result of feeling of the test driver in comparison with the case of a control tire (conventional example 1-1).
  • the reference points for the evaluation are as follows:
  • Each set of test tires were mounted onto rims having a rim size of 7.5 J ⁇ 17, with an air pressure of 300 kPa charged, and the high-speed durability evaluation was performed by the step speed method in conformance with a test method according to JATMA standards.
  • the evaluation result is shown by an index, with the speed at tire failure in the conventional example 1-1 as 100. Higher the numeral value, better is the result.
  • flexural rigidity of each of the test cords was measured by using the taber flexural rigidity tester (the Toyo Seiki Seisaku-sho, Ltd., digital taber type stiffness tester), in a state wherein the code was bent 15 degrees from a fulcrum after having been cut to a length of 90 to 95 mm.
  • the flexural rigidity of a code of which the outer profile shape is flat was defined to be rigidity with respect to bending in the minor axis direction.
  • the flexural rigidity (Ec) of the steel cord that had been taken out from the belt layer of the tire with rubber attached thereto was measured in a state wherein, after the cord with the rubber attached thereto had been taken out, the thickness of a coating rubber on the cord surface was reduced to about 0.1 to 0.5 mm by chipping away the coating rubber.
  • the flexural rigidity (Er) of the cord cleared of the rubber was measured in a state wherein the rubber is completely removed by an organic solvent.
  • the tires according to the embodiments each having a 1 ⁇ n structure composed of 6 to 12 steel filaments stranded in the same direction at the same stranding pitch, with the diameter of the filaments being 0.08 to 0.21 mm, were ascertained to be superior in both steering stability and durability to the tires of the conventional examples and the comparative examples, which do not satisfy the above-described conditions.
  • a pneumatic radial tire was produced in which two layers of crossed steel belt layers 2 a and 2 b each composed of rubberized steel cords, two cap layers 4 , and a pair of layers 5 are arranged in this order from below in the radial direction of the crown part of the carcass.
  • steel cords ones satisfying the conditions in the following tables 3 and 4 were employed.
  • the tire size was set to 225/45R17, and the angle of the crossed belts 2 a and 2 b was set to ⁇ 60° with respect to the width direction of the tire.
  • Nylon cords were applied to the cap layer 4 and the layer tiers 5 . Evaluation was made regarding each test tire obtained in accordance with the following methods. Evaluation results are collectively shown in Tables 3 and 4.
  • the measurements were made by using the digital taber rigidity tester manufactured by Toyo Seiki Seisaku-sho, Ltd., in a state wherein the code was bent 15 degrees from a fulcrum after having been cut to a predetermined length.
  • the flexural rigidity of a code of which the outer profile shape is flat was defined to be rigidity with respect to bending in the minor axis direction.
  • the flexural rigidity (Ec) of the steel cord in a state of being buried in the belt layer was measured in a state wherein, after the cord with the rubber attached thereto cut off from the test tire, the thickness of a coating rubber on the cord surface was reduced to about 0.1 to 0.5 mm by chipping away the coating rubber.
  • the flexural rigidity (Er) of the cord alone in a state of not being buried in the belt layer was measured in a state wherein the rubber on the cord surface with rubber attached thereto, cut off from the test tire, was completely removed by dissolution with an organic solvent.
  • the rubber permeability of each steel cord was evaluated by soaking it in an aqueous 10 percent solution of NaOH, and after 24 hours, the rubber permeability of each of the steel cords was evaluated by checking to see the degree of corrosion by NaOH.
  • corrosion amount becomes 0 (conventional example 2-1), and this is shown by an index of 100. Higher the index, better the result.
  • Each set of test tires was mounted onto four wheels of a passenger car, with an air pressure of 205.8 kPa (2.1 kgf/cm 2 ) charged, and a test driver run this test car on a test course.
  • the steering stability and riding comfort was evaluated by the rating result of feeling of the test driver in accordance with the following criteria, in comparison with the case of a control tire (conventional example 2-1).
  • Each set of test tires was mounted onto rims having a rim size of 7.5 J ⁇ 17, with an air pressure of 300 kPa charged, and the high-speed durability evaluation was performed by the step speed method in conformance with a test method according to the JATMA standards.
  • the evaluation result is shown by an index, with speed at tire failure in the conventional example 2-1 as 100. Higher the numeral value, better is the result.
  • the tire in each of the embodiments using steel cords of which the flexural rigidity (Ec) in a state of being buried in the belt layer is not less than 49 MPa nor more than 196 MPa, and simultaneously, the Ec value is 1.0 to 1.27 times as high as the flexural rigidity (Er) of the steel cords alone in a state of not being buried in the belt layer, was ascertained to have superior steering stability and durability to the tire in each of the comparative examples, which does not satisfy the above-described conditions.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Tires In General (AREA)
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US12/092,198 2005-10-31 2006-10-30 Steel cord for reinforcing rubber article and pneumatic radial tire Expired - Fee Related US8146339B2 (en)

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JP2005315811A JP4716846B2 (ja) 2005-10-31 2005-10-31 空気入りラジアルタイヤ
JP2005-315811 2005-10-31
JP2005359704A JP2007162163A (ja) 2005-12-14 2005-12-14 ゴム物品補強用スチールコードおよび空気入りラジアルタイヤ
JP2005-359704 2005-12-14
PCT/JP2006/321652 WO2007052603A1 (fr) 2005-10-31 2006-10-30 Cable en acier servant a renforcer un article en caoutchouc et pneumatique radial

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Cited By (1)

* Cited by examiner, † Cited by third party
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US20160082776A1 (en) * 2014-09-23 2016-03-24 Kumho Tire Co., Inc. Pneumatic radial tire for a passenger car having ultra fine steel cords for a carcass ply

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* Cited by examiner, † Cited by third party
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WO2009041636A1 (fr) * 2007-09-27 2009-04-02 Bridgestone Corporation Pneu
JP5213160B2 (ja) * 2007-11-29 2013-06-19 株式会社ブリヂストン 空気入りタイヤ
JP5213161B2 (ja) * 2007-11-29 2013-06-19 株式会社ブリヂストン 空気入りタイヤ
JP5121589B2 (ja) * 2008-06-11 2013-01-16 株式会社ブリヂストン ランフラットタイヤ
EP2475818B1 (fr) * 2009-09-11 2014-07-30 NV Bekaert SA Toron ovale de construction m+n comprenant une couche centrale avec au moins un fil ovale
US9073389B2 (en) 2011-10-21 2015-07-07 Bridgestone Americas Tire Operations, Llc All steel fabric radial construction for agricultural tires
JP6072658B2 (ja) * 2013-09-20 2017-02-01 東洋ゴム工業株式会社 空気入りタイヤ
JP7102770B2 (ja) * 2018-02-22 2022-07-20 住友ゴム工業株式会社 空気入りタイヤ
FR3090494A3 (fr) * 2018-12-19 2020-06-26 Michelin & Cie Pneumatique pour véhicule comprenant une structure de rigidification.

Citations (31)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5938102A (ja) 1982-08-30 1984-03-01 Yokohama Rubber Co Ltd:The ラジアルタイヤ
JPS60185602A (ja) 1984-03-05 1985-09-21 Bridgestone Corp 乗用車用空気入りタイヤ
JPS6485383A (en) 1987-09-26 1989-03-30 Bridgestone Corp Tire reinforcing steel cord
JPS6485382A (en) 1987-09-26 1989-03-30 Bridgestone Corp Tire reinforcing steel cord
JPS6485384A (en) 1987-09-26 1989-03-30 Bridgestone Corp Tire reinforcing steel cord
JPS6485381A (en) 1987-09-25 1989-03-30 Bridgestone Corp Radial tire
JPH01141103A (ja) 1987-11-25 1989-06-02 Sumitomo Rubber Ind Ltd 空気入りラジアルタイヤ
JPH0374206A (ja) 1989-08-17 1991-03-28 Bridgestone Corp ラジアルタイヤ
JPH03143703A (ja) 1989-10-27 1991-06-19 Sumitomo Rubber Ind Ltd ラジアルタイヤ
JPH05302283A (ja) 1992-04-20 1993-11-16 Tokyo Seiko Co Ltd ゴム補強用スチールコード
JPH0610281A (ja) 1992-06-22 1994-01-18 Tokyo Seiko Co Ltd ゴム補強用スチールコード
JPH0673673A (ja) 1992-08-24 1994-03-15 Tokyo Seiko Co Ltd ゴム補強用スチールコード
JPH07279067A (ja) 1994-04-04 1995-10-24 Tokyo Seiko Co Ltd ゴム補強用スチールコードおよびその製造法
JPH07331587A (ja) 1994-06-03 1995-12-19 Tokyo Seiko Co Ltd 高伸度スチールコード及びこれを用いたラジアルタイヤ
JPH0892884A (ja) 1994-09-26 1996-04-09 Tokyo Seiko Co Ltd ゴム補強用スチールコードおよびこれを使用したタイヤ
JPH08113886A (ja) 1994-10-17 1996-05-07 Tokyo Seiko Co Ltd タイヤ補強用スチールコード及びこれを用いたラジアルタイヤ
JPH09209283A (ja) 1996-01-31 1997-08-12 Tokyo Seiko Co Ltd ゴム補強用スチールコードおよびラジアルタイヤ
JPH09268485A (ja) 1996-01-26 1997-10-14 Tokyo Seiko Co Ltd ゴム補強用スチールコードおよびラジアルタイヤ
JPH09279493A (ja) 1996-04-12 1997-10-28 Tokyo Seiko Co Ltd ゴム製品補強用スチールコード及びゴム複合体
JPH09279492A (ja) 1996-04-12 1997-10-28 Tokyo Seiko Co Ltd ゴム製品補強用スチールコード及びラジアルタイヤ
US5737909A (en) * 1996-03-11 1998-04-14 The Goodyear Tire & Rubber Company Metallic cord for the reinforcement of elastomers
JPH10250310A (ja) 1997-03-14 1998-09-22 Yokohama Rubber Co Ltd:The 重荷重用空気入りラジアルタイヤ
JPH10292277A (ja) 1997-04-10 1998-11-04 Tokyo Seiko Co Ltd スチールコードおよびタイヤ
JPH10298880A (ja) 1997-04-23 1998-11-10 Tokyo Seiko Co Ltd スチールコード及びタイヤ
JPH11323748A (ja) 1998-05-12 1999-11-26 Tokyo Seiko Co Ltd スチールコード
JPH11335985A (ja) 1998-05-29 1999-12-07 Tokyo Seiko Co Ltd スチールコードおよびラジアルタイヤ
JPH11350367A (ja) 1998-06-03 1999-12-21 Tokyo Seiko Co Ltd スチールコード及びスチールラジアルタイヤ
EP0985760A2 (fr) 1998-09-10 2000-03-15 Hankook Tire Co., Ltd. Câble d'acier pour pneumatique radial
US6365273B1 (en) * 1989-02-06 2002-04-02 N.V. Bekaert S.A. Compact cord
JP2003063209A (ja) 2001-08-27 2003-03-05 Bridgestone Corp コード補強部材及びその製造方法並びに空気入りタイヤ
US20050133140A1 (en) * 2003-12-23 2005-06-23 Hongduk Steel Cord, Co. Ltd., And Kumho Tire Co., Inc. Steel cord having ultrafine steel filaments to reinforce tire carcass and radial tire for passenger car using the same

Patent Citations (31)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5938102A (ja) 1982-08-30 1984-03-01 Yokohama Rubber Co Ltd:The ラジアルタイヤ
JPS60185602A (ja) 1984-03-05 1985-09-21 Bridgestone Corp 乗用車用空気入りタイヤ
JPS6485381A (en) 1987-09-25 1989-03-30 Bridgestone Corp Radial tire
JPS6485383A (en) 1987-09-26 1989-03-30 Bridgestone Corp Tire reinforcing steel cord
JPS6485382A (en) 1987-09-26 1989-03-30 Bridgestone Corp Tire reinforcing steel cord
JPS6485384A (en) 1987-09-26 1989-03-30 Bridgestone Corp Tire reinforcing steel cord
JPH01141103A (ja) 1987-11-25 1989-06-02 Sumitomo Rubber Ind Ltd 空気入りラジアルタイヤ
US6365273B1 (en) * 1989-02-06 2002-04-02 N.V. Bekaert S.A. Compact cord
JPH0374206A (ja) 1989-08-17 1991-03-28 Bridgestone Corp ラジアルタイヤ
JPH03143703A (ja) 1989-10-27 1991-06-19 Sumitomo Rubber Ind Ltd ラジアルタイヤ
JPH05302283A (ja) 1992-04-20 1993-11-16 Tokyo Seiko Co Ltd ゴム補強用スチールコード
JPH0610281A (ja) 1992-06-22 1994-01-18 Tokyo Seiko Co Ltd ゴム補強用スチールコード
JPH0673673A (ja) 1992-08-24 1994-03-15 Tokyo Seiko Co Ltd ゴム補強用スチールコード
JPH07279067A (ja) 1994-04-04 1995-10-24 Tokyo Seiko Co Ltd ゴム補強用スチールコードおよびその製造法
JPH07331587A (ja) 1994-06-03 1995-12-19 Tokyo Seiko Co Ltd 高伸度スチールコード及びこれを用いたラジアルタイヤ
JPH0892884A (ja) 1994-09-26 1996-04-09 Tokyo Seiko Co Ltd ゴム補強用スチールコードおよびこれを使用したタイヤ
JPH08113886A (ja) 1994-10-17 1996-05-07 Tokyo Seiko Co Ltd タイヤ補強用スチールコード及びこれを用いたラジアルタイヤ
JPH09268485A (ja) 1996-01-26 1997-10-14 Tokyo Seiko Co Ltd ゴム補強用スチールコードおよびラジアルタイヤ
JPH09209283A (ja) 1996-01-31 1997-08-12 Tokyo Seiko Co Ltd ゴム補強用スチールコードおよびラジアルタイヤ
US5737909A (en) * 1996-03-11 1998-04-14 The Goodyear Tire & Rubber Company Metallic cord for the reinforcement of elastomers
JPH09279493A (ja) 1996-04-12 1997-10-28 Tokyo Seiko Co Ltd ゴム製品補強用スチールコード及びゴム複合体
JPH09279492A (ja) 1996-04-12 1997-10-28 Tokyo Seiko Co Ltd ゴム製品補強用スチールコード及びラジアルタイヤ
JPH10250310A (ja) 1997-03-14 1998-09-22 Yokohama Rubber Co Ltd:The 重荷重用空気入りラジアルタイヤ
JPH10292277A (ja) 1997-04-10 1998-11-04 Tokyo Seiko Co Ltd スチールコードおよびタイヤ
JPH10298880A (ja) 1997-04-23 1998-11-10 Tokyo Seiko Co Ltd スチールコード及びタイヤ
JPH11323748A (ja) 1998-05-12 1999-11-26 Tokyo Seiko Co Ltd スチールコード
JPH11335985A (ja) 1998-05-29 1999-12-07 Tokyo Seiko Co Ltd スチールコードおよびラジアルタイヤ
JPH11350367A (ja) 1998-06-03 1999-12-21 Tokyo Seiko Co Ltd スチールコード及びスチールラジアルタイヤ
EP0985760A2 (fr) 1998-09-10 2000-03-15 Hankook Tire Co., Ltd. Câble d'acier pour pneumatique radial
JP2003063209A (ja) 2001-08-27 2003-03-05 Bridgestone Corp コード補強部材及びその製造方法並びに空気入りタイヤ
US20050133140A1 (en) * 2003-12-23 2005-06-23 Hongduk Steel Cord, Co. Ltd., And Kumho Tire Co., Inc. Steel cord having ultrafine steel filaments to reinforce tire carcass and radial tire for passenger car using the same

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
Anonymous; "High Tensile Strength Steel Cord Constructions for Tyres," Research Disclosure, Aug. 1, 1992, Mason Publications, Hampshire GB, XP007118007 ISSN: 0374-4353, 20 pages.
English language translation of JP 11-323748, Nov. 26, 1999, Tokyo Seiko Co., Ltd.
Supplementary European Search Report issued in European Patent Application No. 06 81 2162, dated Jan. 5, 2010 (1 page).

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20160082776A1 (en) * 2014-09-23 2016-03-24 Kumho Tire Co., Inc. Pneumatic radial tire for a passenger car having ultra fine steel cords for a carcass ply
US9840114B2 (en) * 2014-09-23 2017-12-12 Kumho Tire Co., Inc. Pneumatic radial tire for a passenger car having ultra fine steel cords for a carcass ply

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